Boot requirement.....

Hi, My requirement: I have a board with a daughter board on it. Motherboard(MB) has a IDE hard disk. Daughterboard(DB) has IUSB flash disk. The communication between the 2 boards is via PCI bus. Daughterboard is like a slave to the Motherboard.MB has the OS as psos. Daughter board have Linux on it.(no other OS)

The issue is how to bring up the daughter board.

My analysis: Since the DB has the flash disk(Assume it is formatted), it has to boot using some standard bootloader such as LILO/GRUB. I mean to say that we cannot follow the procedure meant as the part of bootsect.s file as this is meant for booting from floppy.Also this file is obsolete from 2.6 kernel onwards!.

Initially, BIOS will get the linux image from the MB hard disk through PCI interface. Now, the BIOS shall jump to the MBR of the flash disk (BIOS have the drivers to access the flash disk) and execute stage1 of the bootloader(assume if i use GRUB), then, for it to load and run the linux image, it searches the /boot directory for the linux image. This means that the stage1 of the bootloader should be aware of the file sytem. Who creates the file system?? Also, for the BIOS to put the image on the flash disk, it should know the file system format!!!. Isnt it? Does this mean the BIOS should create the file system??

Assume if my requirement is that i should NOT create the file system manually before i put the flash disk in to the DB. It should be taken care through some other means. (or) the only way out without too many hurdles is to create file system manually on the flash disk.

Thanks Uday

Reply to
Uday Mullangi
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How will the BIOS get the linux image from the MB hard disk? Normally the bootloader does this.

If you already have loaded the kernel image, why do you need a bootloader?

With GRUB as a boot loader, stage1 is ignorant of file systems, there are a number of stage1_5 images which have limited file system awareness and fit into a 512 Byte boot sector. Stage 2 image knows all, but resides on the boot file system.

Uday Mallangi creates the file system.

What image do you need to put on the flash disk?

The BIOS will not create a file system for you.

Assuming that you do not want to create a file system before you put a flash disk in to the DB, I think you already answered your question above where you wrote: "Initially, BIOS will get the linux image from the MB hard disk through PCI interface." You won't have a bootloader on the flash because the flash will be empty (your pre-condition).

Read this link and see if it helps your thinking:

formatting link

Reply to
Craig Bergren

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